Use whatever you can get the best deal on.
After you have some experience with it, try the other type.
Go from there.
Don't ever look at different cases thinking, "I'll be able to load XXX brand hotter than YYY." It doesn't work like that, and you'll be chasing a fantasy. There are a few special exceptions; but they generally only involve soft brass, such as Federal and Norma, which see case head stretching before many other brands.
Personally, I consider (US) military .308 and .30-06 to be some of the best brass available, short of premium stuff (Norma, Lapua, etc.). But, that's just my opinion, and it's not based on case life or pressure tolerance -- It's much more consistent than most commercial brass.
"Such is the strange way that man works -- first he virtually destroys a species and then does everything in his power to restore it."